The ideal gas equation is given by:
PV = nRT
Where: P is the pressure of the gas V is the volume of the gas n is the number of moles of the gas R is the ideal gas constant T is the temperature of the gas
To calculate the molecular weight (molar mass) of chloroform, we need to find the number of moles (n) of chloroform using the ideal gas equation.
Given: P = 101.3 kPa V = 127 cm³ = 0.127 dm³ (converted from cubic centimeters to cubic decimeters) T = 75 °C
We need to convert the temperature from Celsius to Kelvin by adding 273.15:
T = 75 °C + 273.15 = 348.15 K
The ideal gas constant, R, is approximately 8.314 J/(mol·K).
Rearranging the ideal gas equation to solve for n:
n = PV / (RT)
Substituting the given values:
n = (101.3 kPa) * (0.127 dm³) / [(8.314 J/(mol·K)) * (348.15 K)]
Now, let's calculate n:
n ≈ (101.3 kPa * 0.127 dm³) / (8.314 J/(mol·K) * 348.15 K)
Converting kilopascals to pascals:
n ≈ (101300 Pa * 0.127 dm³) / (8.314 J/(mol·K) * 348.15 K)
Simplifying the units:
n ≈ (12,891.9 J·dm³) / (2,894.49 J·mol⁻¹)
n ≈ 4.458 mol
We have found that the number of moles of chloroform is approximately 4.458 mol.
The molecular weight (molar mass) of chloroform can be calculated using the formula:
Molar mass = mass / moles
Given the mass of chloroform is 0.53 g:
Molar mass = 0.53 g / 4.458 mol
Molar mass ≈ 0.119 g/mol
Therefore, the molecular weight (molar mass) of chloroform (CHCl3) is approximately 0.119 g/mol.